Home Science Experiment: sediment density and gravity separation. In an effort to discover the best way to consistently grind coffee

When I make coffee in the morning, I have a technique of grinding beans which I have assumed gives a more consistent grind for our French Press. A consistent grind is necessary because when the grind is too large, the coffee is weak, and when the grind is too small, the coffee is grainy with sediment. The problem is that our grinder is the sort with a single chamber with blades at the bottom, so the it continues to grind all of the coffee at the bottom of the chamber, whether it is fine, coarse, or whole bean. When I grind coffee, I run the grinder in short bursts while grinding and shaking the grinder up and down (this, in theory, prevents the fine grains from getting stuck on the bottom with the blades, so that all the beans our ground more evenly). John runs the grinder in short bursts while turning the grinder upside down and right side up again (this, in theory, more evenly distributes the beans and grounds so that gravity doesn't separate them naturally and the fine grounds don't get stuck on the bottom with the blades while the beans stay on top waiting to be ground). These methods of grinding created a debate: does shaking help to prevent over grinding, or does aid in the natural separation of gravity and density to keep the whole beans from reaching the grinder? Do we remember how separation of sediment works? This debate was followed by a google search and then the decision to experiment ourselves; enough with the incomprehensible if not inapplicable diagrams of google images!

To begin, we ground some beans very fine in the grinder (by holding the grind button down and waiting until all of the beans had been processed); we ground some beans coarse (by wrapping them in a towel and pounding them with the bottom of a mug); and left some beans unground. Next, we put all the beans in a glass jar (after some debate about the best way to make a paper funnel). Finally, we took turns shaking the glass jar several ways (upside down, right side up, sideways, in a swirling motion, etc.).

The result? The whole beans consistently rose to the top, and the fine grains descended to the bottom (which makes sense, given thought about the concepts of gravity, density, and surface area, but is nice to see confirmed by experimentation).

Further research is needed to determine the best way to grind beans evenly (Proposed method: keeping the grinder upside down and shaking so that the beans that are naturally on top are ground. Possible objection: could rough handling and dry running cause damage to the internal workings of the grinder?). Further research is also needed to determine whether shaking really helps or hurts (N.H. Shaking does nothing. H.1 Shaking causes the fine grounds to continue to be ground while keeping the whole beans away from the blades. H.2 Shaking keeps the fine grounds from packing together on the bottom and allows the whole beans to move around and come into contact with the blades sooner than doing nothing).